The present invention relates to a nasal dilator and, more particularly, to an outboard nasal dilator and mask-integrated nasal dilator for reducing nasal airway resistance.
Nasal airway resistance causes an increased breathing effort and also promotes mouth breathing. Nasal breathing is preferable in most day-to-day circumstances because the nose provides a means to filter incoming air by trapping atmospheric pollutants in the nasal passage hairs and inner nostril mucosa (sticky) membrane before the air enters the lungs. The nasal passages also provide a means to warm and moisturize incoming air to provide breathing comfort. Increased nasal resistance can deprive patients of air and oxygen.
Where nasal positive airway therapy devices are used such as with continuous positive airway pressure (CPAP) or other non-invasive positive pressure ventilation (NIPPV) devices to treat patients with Obstructive Sleep Apnea (OSA), an increase in nasal flow resistance will affect therapy by increasing work of breathing and by increasing pressure swings. Swings reflect the variation in pressure that the patient experiences when breathing; the lower the swings, the more comfortable it is to breathe by the patient. Nasal resistance has been well documented to negatively impact the effectiveness of CPAP therapy and patient compliance. Many people suffer from seasonal allergies and congestion due to upper respiratory problems associated with colds, flu or rhinitis. Based on Poiseuilles Law, one can clearly see the impact resistance has on pressure and flow curves. If the main conduit for CPAP is via the nasal passage, and resistance changes by even a small amount, the effective pressure delivered to the patient's airway is potentially compromised and could result in sub-therapeutic pressures being delivered to the patient. A commonly recognized phenomenon during REM sleep is phasic nasal breathing whereby the turbinates rest, and breathing flow gradually switches from one nare to the other during the night. In some patients this could have a significant effect on their apnea/hypopnea index (AHI) during the most vulnerable period of sleep.
The nasal passage region that is most likely to create airflow resistance is around the region known as the nasal vents. This is where the cross-sectional area of the nasal passage is narrowest and also susceptible to narrowing. The nasal vents coincide with a region in the soft-tissue nasal passages that is approximately just below the nasal bone on either side if the nose (or nasal bridge). Current art such as the “Breathe-Right™” nasal strips intend to open the nasal passages in the nasal vent region.
There are other types of devices that are attached to the sides of the nose. One such device is a nasal dilator that does not fit over the bridge of the nose but is attached to each side of the nose by self-adhesive tape. See, for example, U.S. Pat. No. 6,228,101 and U.S. Pat. No. 6,663,649.
Numerous devices and current art assist to reduce nasal resistance in the nasal vent region and physically and mechanically cause the nasal passages to dilate or open further in their internal cross-sectional area. These nasal dilator mechanical devices assist in soft-tissue dilation by splinting the nasal passages open further either internally, e.g., by way of outwardly tensioned springs, to external devices as previously mentioned that are attached to the outside surface of the nose by adhesive or by some other mechanical fastener.
The problem with current art is that they do not recognize that the exterior and interior of the nose is sensitive to contact and also contact pressure. For example, the interior of the nose contains nasal hairs and soft-tissue membranes that are sensitive to being brushed against with physical devices.
Also considering the exterior of the nose, devices that attach by adhesives or self-adhesives are not ideal as the adhesives are designed to be a compromise on a secure fit and the ability to remove them easily from the skin after use. The skin surface on the nose is particularly sensitive to touch and generally more so than the surrounding exterior surfaces on the face or head.
Any nasal dilator and any mechanical contact with the nose (internally or externally) may cause irritation to a patient.
A further disadvantage of current art devices is their inability to be combined or integrated into a nasal mask system when the patient is prescribed with a mask interface such as when used with positive airway pressure therapy such as CPAP. It would provide great user convenience for mask wearers to minimize the number of operations or steps required to have both nasal dilation and proper fit of a mask interface.
Current art requires a cumbersome initial installation of the nasal dilator and subsequently the mask interface. Other designs utilize tensioning springs that sit over the nose, which may also interfere with the nasal mask interface. Furthermore, any material that rests between the sealing surface of a nasal mask cushion seal and the face may affect sealing performance of the mask and thereby affect treatment.